Method of producing sprinkly colored fibrous material



Uitc

US. Cl. 57-164 6 Claims ABSTRACT OF THE DISCLOSURE Methods of producing sprinkly colored yarns or yarns capable of being so dyed, which comprises gathering together, drawing and twisting together yarns (A) and (B) wherein yarn (B) is one which either has been dopedyed or has a higher dyeability than yarn (A), with the proviso that the yarns (A) and (B) are those which, upon being drawn, possess the properties that the elongation of the latter is 39% greater than that of the former and the denier ratio of the former to the latter ranges between 121 and 3:1.

This invention relates to a method of producing sprinkly colored fibrous materials. More particularly, the invention relates to a method of producing yarns and fabrics of sprinkly colored synthetic fibers or yarns and fabrics having the potentiality of being dyed to such a tone.

Heretofore, as one of the methods of producing sprinkly colored yarn, there is known that in which a twisted yarn dyed to a certain shade and that which is either undyed or dyed to another shade are combined and crimped with a crimping apparatus. Another method is that in which twisted yarns composed of different classes of material fibers are combined and crimped, after which the composite yarn is dyed with a dyestuff which dyes one of the material fibers but not the other. However, in these methods, the initial twist possessed by each of the original yarns to be combined and the twist resulting from their untwisting have a great effect such that the composite product has the character of a plied yarn.

Hence, the different yarns are not present evenly in this composite yarn or in a fabric knitted or woven therefrom but rather in a discrete fashion, with the consequence that spottiness in the pattern occurs and the sprinkly colored pattern displayed is of a confused pitch. As still another method, one in which the drawing and twisting together of different classes of undrawn multifilament yarns are carried out simultaneously has been attempted. In a method such as this, only unsatisfactory products could be obtained however, because of the difference in drawability between the different classes of multifilament yarns which gave rise to either filament breaks during the processes of twisting the yarns together or to slacks and strains to result in nonuniformity of the twist.

As a result of much investigation with a view to eliminating the various drawbacks of the conventional methods such as hereinabove described, we found that in gathering together, drawing and twisting together an undrawn synthetic multifilament yarn and a dope dyed undrawn synthetic multifilament yarn, very desirable sprinkly colored yarns could be obtained by specifying, as hereinafter to be described, the elongation possessed by the two multifilament yarns and the denier ratio States Patent M 3,468,121 Patented Sept. 23, 1969 thereof. The so obtained yarn has a beautiful appearance as well as the feature that it is not easily discolored by means of abrasion. It was also found that a yarn capable of being dyed a sprinkly tone could be obtained in similar manner from an undyed, undrawn synthetic multifilament yarn and an undrawn synthetic multifilament yarn having a higher dyeability than that of the former.

It is therefore an object of this invention to provide a method of producing from undrawn synthetic multifilament yarns sprinkly colored yarns of uniform sprinkly colored pattern or yarns which can be so dyed, the production of which is accomplished evenly without giving rise to hardly any filament breaks or accompaniment of slacks or strains in the filaments.

One mode of this invention consists of a method of producing sprinkly colored yarns, which comprises gathering together an undrawn synthetic multifilament yarn (A) and a dope-dyed undrawn synthetic multifilament yarn (B) and thereafter drawing and twisting the yarns together, with the proviso that the yarns (A) and (B) are those which, upon being drawn, possess the properties that the elongation of the latter is 39% greater than that of the former and the denier ratio of the former to the latter is 1:1-3: 1.

Another mode of the invention consists of a method of producing yarns which can be dyed to a sprinkly colored pattern, which comprises gathering together an undrawn synthetic multifilament yarn (A) and an undrawn synthetic multifilament yarn (B) of higher dyeability than that of yarn (A) and thereafter drawing and twisting the yarns together, with the proviso that the yarns (A) and (B) are those which, upon being drawn, possess the properties that the elongation of the latter is 39% greater than the former and the denier atio of the former to the latter is 1:1-3: 1.

For a better understanding of this invention, it will be more fully described'hereinafter with reference being had to the results of experiments which were conducted during our investigation.

First, as a typical example, the drawing and twisting together of a. white polyethylene terephthalate multifilament yarn and a dope-dyed polyethylene terephthalate multifilament yarn will be described. The term white yarn, as here used, denotes an undyed white colored yarn which may or may not contain a small quantity of titanium dioxide, while the term dope dye yarn denotes a colored yarn which has been obtained by spinning a molten polymer containing a pigment. In making a yarn by drawing these two yarns and twisting them together, the main troubles that are encountered are: (a) that filament breaks occur or slacks and strains occur in the filaments during the yarn making process; and (b) that there is a difference in the sprinkly colored tones between each of the woundup pirns.

One example of the results that were obtained by an experiment of ours when we were investigating into the cause of these troubles is presented below.

Polyethylene terephthalate having an inherent viscosity of 0.60 and containing 2% of titanium dioxide as a delustrant and polyethylene terephthalate having an intrinsic viscosity of 0.60 and containing 3.2% of a blue pigment were each separately melt-spun under their respective optimum melt-spinning conditions at a speed of 1000 meters per minute at 20 grams per minute to obtain respectively a white undrawn multifilament yarn and a dope-dyed undrawn multifilament yarn. Three classes of yarns were made by drawing and twisting these two multifilaments alone as well as together. The elongation of these two multifilaments, after drawing, was in either case 26% and the denier of all three product yarns was 50 deniers. The

results obtained after spinning for 24 hours using 150 spindles are shown in Table I.

less if the difference in the elongations (percent) between the white yarn and the dope-dyed blue yarn is 39%.

TABLE I Number of spindles in which breaks Number of (including Number of spindles in flufls) spindles Tenacity, Elongation, which slacks occurred in Yarn Xtirne, hr. g./d. percent ocurred filament Composite yarn 150x24 4. 7 24 2 23 White yarn alone 150x24 4. 8 26 None 1 Dope-dyed blue yarn alone..- 150x24 4. 8 26 None 1 1 Blue yarn. 2 White yarn.

As apparent from the results given in the foregoing table, the drawability of the yarn is very inferior in the case of that consisting of two components twisted together as compared with that of the two components when used alone. From these results, it is seen that in the composite twisted yarn the slacks of the white yarn and the filament breaks of the dope-dyed blue yarn are very numerous. The cause for this is believed to be due to the fact that the rate of shrinkage of the dope-dyed blue yarn immediately prior to its being wound up on a pirn is greater than that of the white yarn. Namely,

TABLE III Difierence in elongation (percent) between the Number of slacks Number of filament breaks dope-dyed blue yarn X X and white yarn (average) Max. Min. (average) Max. Min.

16 21 3 13 20 o 9 17 0 s 13 2 a 5 0 2 6 0 1 a 0 2 4 2 2 4 0 1 2 0 1 2 0 a 5 7 3 5 0 1 3 0 2 4 0 2 6 0 5 8 1 4 7 0 19 28 11 11 21 0 45 65 34 29 41 0 since the drawing tension prior to the draw rolls is greater Thus, it was found from the foregoing results that a than the tension between the draw rolls and the windup, uniform composite twisted yarn having few filament slacks the yarn becomes somewhat relaxed subsequent to the and breaks could be obtained by raising the elongation draw rolls and the difference in the shrinkage of the white of the doper-dyed blue yarn 3-9% above that of the yarn and the dope-dyed blue yarn in this state worsens White yarn. The difference in the inherent viscosity of the the drawability. We found that for eliminating the appolymers of the several multifilament yarns before meltpearance of this trouble which was ascribable to the difp mg 18 not partlcularly a problem, since it can be ference in the relaxation and shrinkage of the two comcompensated y adlusmlent 0f the Spinning P Again, ponents under identical drawing conditions it was neces- 11116 00101 f t dope-dyed yarn can be freely chosen, sary to use a yarn of higher elongation in the case of that $11611 black, f brown, Further, there is having a higher relaxation and shrinkage, i.e., to use as practlcally I10 dlfferenqe 111 Youngs IIlOdllluS Of these the blue yarn one of higher elongation than that of the drawn Y as shown In Table IV be owwhite yarn, and hence we conducted the following series of experiments.

TABLE The previously described starting material was used Iv and by varying the spinning temperature in carrying out Elongation nmdulus of dope-dyed Yam the melt-spinning of dope-dyed blue yarns multifilament Percent; Blue Black Red Green Brown yarns having various elongations were made. When these 10 1,350 1,350 1,348 1,346 1,35 yarns were twisted together with white yarn, the results 1,301 1,300 1,298 1,297 1,30 shown in Table 11, below, were obtained. 282 278 TABLE II Difierence in Numbe oi Elongation oi Elongation of the percentages Number 01' spindles in giiiiiii i iii white yarn, dope-dyed blue of the spindles which slacks which filament percent yarn, percent elongation Xtime, hr; occurred breaks occurred 27 1 150x24 25 2s 2s 2 150x24 15 11 29 3 150x24 2 1 s0 4 150x24 1 2 a1 5 150x24 2 2 as 7 150x24 1 1 35 9 150x24 5 4 36 10 150x24 21 15 37 11 150x24 48 23 Thus, it is apparent from the foregoing results that the Next it was found that the trouble (b) previously deoccurrence of slacks and number of filament breaks are scribed, i.e., spottiness in the sprinkly colored tones of the woundup pirns, could be solved by adjusting the ratio of the denier of the white multifilament yarn used to that of the dope-dyed multifilament yarn used. In twisting together a dope-doped yarn containing 3.2% of black pigment (elongation 33%) and white yarn (elongation 28%), the denier ratio of two components were varied. One hundred and fifty ends of the so obtained yarns, after being wound up on pirns, were visually examined, with the results shown in Table V, below.

i The method of examination consisted of visually examining the 150 pirns arranged side by side and picking up those which were either blacker or whiter than the standard, which was established for each denier ratio used. The numerals in the table indicate the number of pirns.

TAB LE V Denier ratio whitecblaek Thus, it was found that when the denier ratio of white yarn to dope-dyed black yarn was within the range 1:1-3z1 an exceedingly stable color tone was exhibited.

It can be understood from the results of the various and numerous experiments hereinbefore presented that for obtaining sprinkly colored yarns which are even and without any spottiness in the sprinkly colored tone it is very important to specify the difference in elongation between the white and dope-dyed multifilament yarns as well as the denier ratio of the two yarns. The desired product of good quality cannot possibly be obtained by ignoring these two factors and just twisting the two multifilament yarns together. Although the aforementioned experiments were those carried out on the polyester type multifilament yarn, similar results are also obtained with respect to the other synthetic fibers, such, for example, as the polyamide, polyacrylonitrile and polyolefin type multifilament yarns. By knitting or weaving the so obtained sprinkly colored yarn, fabrics having a highly desirable sprinkly colored pattern are obtained. When this type of yarn or fabric is further overdyed, a sprinkly colored fibrous material of the desired tone can be obtained in accordance with the dyestuif used.

While the description given hereinbefore has concerned the twisting together of a white multifilament yarn and a dope-dyed multifilament yarn, we found that entirely identical conditions can be applied when twisting together two classes of white multifilament yarns whose dyeability differs. Thus, when an undrawn synthetic multifilament yarn of low dyeability and an undrawn synthetic multifilament yarn of higher dyeability are gathered together, drawn and twisted together, a yarn which can be dyed an even sprinkly colored pattern is made without appearance of slacks and breaks in the filaments provided that the yarns are chosen so that the elongation of the latter is 39% greater than that of the former and the denier ratio of the former to the latter is 1:1-3: 1. When so obtained yarn or the fabrics knitted or woven therefrom are dyed using the conventional dyeing methods, sprinkly colored fibrous materials of the desired tones can be obtained.

In general, as the synthetic fiber of low dyeability, filaments of homopolymers are used, whereas as the synthetic fiber of high dyeability, filaments of copolymers, which have been prepared to enhance the dyeability, are used. Various fiber-forming copolymers, which have been prepared for enhancing the dyeability, are widely known. The comonomeric components used for making this type of copolymer include, in the case of the polyester type, such, for example, as adipic acid, sebacic acid, o-phthalic acid, isophthalic acid, sodium-S-sulfoisophthalate, polyethylene glycol, propylene glycol, polypropylene glycol, polypropylene glycol ethylene oxide addition product, and others; in the case of the acrylonitrile type, such, for

example, as styrene sulfonic acid, sodium styrene sulfonate and others; in the case of the polyolefin type, such, for example, as the vinyl monomers as vinyl pyridine, vinyl carbazole, vinyl quinoline, acrylonitrile, methyl acrylate, methyl methacrylate and vinyl acetate.

According to this invention, excellent sprinkly colored yarn, which had hitherto been unobtainable, can be readily obtained from two classes of undrawn multifilament yarns, using a single drawing and spinning machine.

For a better understanding of this invention, the following nonlirnitative examples are given.

EXAMPLE 1 Polyethylene terephthalate containing 1% titanium dioxide was melt-spun at a spinning temperature of 298 C. and a spinning speed of 1200 meters per minute and a white undrawn multifilament yarn of 175 total denier-24 filaments was obtained. On the other hand a dope-dyed black undrawn multifilament yarn of total denier-8 filaments was made by melt-spinning polyethylene terephthalate containing 3.2% of carbon black at a spinning temperature of 286 C. and a spinning speed of 700 meters per minute. These two yarns were gathered together and were drawn 3.5x (the elongation after drawing was 28% for the former and 33% for the latter) and twisted together using a conventional drawing and spinning machine to obtain ends of a 70D-32F yarn. The rate of occurrence of slacks was 1.3% and the rate of occurrence of filament breaks was 0%. The sprinkly colored pattern of black and white was very evenly distributed over the whole of the yarn.

Control.A dope-dyed black yarn made in the same manner except that it was melt-spun at a spinning speed of 900 meters per minute had an elongation which showed hardly any difference from that of the aforesaid white yarn. When these two yarns were drawn and twisted together in similar manner, the rate of occurrence of slacks of 150 ends of the yarn was 15% while the rate of filament breaks was 7%. Furthermore, the sprinkly colored pattern was not as even as that obtained in the foregoing example.

EXAMPLE 2 150 ends of a 60D-30F sprinkly colored yarn were prepared by drawing and twisting together a white polyethylene terephthalate multifilament yarn containing 4.1% of titanium dioxide (40Dl8F, tenacity 5.0 g./d., elongation 27%) and a dope-dyed blue polyethylene terephthalate multifilament yarn containing 6.3% of Phthalocyanine Blue (20D-l2F, tenacity 4.8 g./d., elongation 33%). The so obtained yarn was then processed with a false twisting machine CS9R and knitted into a jersey. When the irregularity of the color tone was examined, it was only 0.7%.

Control.-When 150 ends of sprinkly colored yarns were prepared by drawing and twisting together the aforesaid white and dope-dyed blue yarns with the denier ratio of the former to the latter being 20 deniers to 40 deniers and thereafter the color tone irregularity was checked by the same method, there were present 12 ends (8%) which were irregular.

EXAMPLE 3 EXAMPLE 4 The yarn obtained in Example 2 was processed and then knitted into a jersey, as described in Example 3. When this jersey was dyed using the commercially avail- EXAMPLE A 157.5 denier undrawn polyethylene terephthalate yarn of 12 filaments and a 105 denier undrawn yarn of 12 filaments of copolymeric polyethylene terephthalate containing 5 mol percent of sebacic acid (based on the dimethyl terephthalate) were drawn and twisted together at a drawing speed of 435 meters per minute and a draw ratio of 3.5x (the tenacity elongation and shrinkage after drawing were 4.9 g./d., 29% and 7% for the former and 4.5 g./d., 34% and 9% for the latter) to obtain a 75D 24F drawn yarn. When this yarn was rewound with a cheese winder to a softness equalling a rubber hardness of 40 degrees and the cheese was dyed for 90 minutes at 100 C., a bath ratio 1:50 and 2% O.W.F., using the commercially available dyestufi Cibacet Blue 2R (C.I. 61110), a sprinkly colored yarn of evenly dyed tones of deep and light blue was obtained, the copolymeric yarn being dyed deep and the common yarn being dyed light.

EXAMPLE 6 The yarn obtained in Example 5, but before dyeing, was used and a tafetta fabric was woven. When this was dyed for 20 minutes at 100 C., a bath ratio 1:100 and 1% O.W.F., using the commercially available dyestutf Fast Green 3B (CI. 55060), an evenly dyed sprinkly colored fabric having a pattern of deep and light green tones was obtained.

We claim:

1. A method of producing a sprinkly colored yarn which comprises gathering an undrawn synthetic multifilament yarn (A) and an undrawn dope-dyed synthetic multifilament yarn (B); drawing the gathered yarns so that the elongation of (B) is 3-9% greater than that of (A) and the denier ratio of (A) to (B) is between 1:1 and 3:1; and thereafter twisting the drawn yarns together.

2. A method of producing a sprinkly colored yarn which comprises gathering an undrawn synthetic multifilarnent yarn (A) and an undrawn dope-dyed synthetic multifilament yarn (B) of higher dyeability than that of synthetic multifilament yarn (A); drawing the gathered yarns 50 8 that the elongation of (B) is 3-9% greater than that of (A) and the denier ratio of (A) to (B) is between 1:1 and 3:1; and thereafter twisting the drawn yarn together.

3. A method of producing a fibrous product having a sprinkly colored pattern which comprises over-dyeing the yarns obtained by the method of claim 1.

4. A method of producing a fibrous product having a sprinkly colored pattern which comprises dyeing the yarn obtained by the method of claim 2.

5. A method of producing a fibrous product having a sprinkly colored pattern which comprises making a fabric from the yarns obtained by the method of claim 1 and subsequently overdyeing said fabric.

6. A method of producing a fibrous product having a sprinkly colored pattern which comprises making a fabric from the yarns obtained by the method of claim 2 and subsequently dyeing said fabric.

References Cited UNITED STATES PATENTS 2,278,888 4/ 1942 Lewis. 2,461 ,094 2/ 1949 Taylor. 2,805,465 9/1957 Miller 57-140 XR 2,904,953 9/ 1959 Groombridge et al. 57-140 XR 3,022,132 2/1962 Shaw 264-290 XR 3,053,604 9/1962 Womble 28-75 XR 3,061,998 11/1962. Bloch 57-140 3,137,989 6/1964 Fior et a1. 57-140 3,375,651 4/ 1968 Greeson 28-75 XR FOREIGN PATENTS 719,046 10/ 1965 Canada. 1,338,199 11/1962 France. 1,423,757 11/1965 France. 1,059,567 2/ 1967 Great Britain.

JORDAN FRANKLIN, Primary Examiner WERNER H. SCHROEDER, Assistant Examiner US. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION patent 3,468 ,121 Dated September 23, 1961 Hirotaka Nakashima et a1. Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, (Table IV), lines 56, 57 and 58 (under last column of table entitle "Brown") line 56 should read 1,3S4 in lieu of "1,35".

line 57 should read 1,305 in lieu of "1,30". line 58 should read 1,286 in lieu of "1,28".

Signed and sealed this 31st day of August 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Acting Commissioner of Paten FORM PO-1050 (10-591 USCOMWDC 50375-95: 

